Flavoring agent

ABSTRACT

The enhancement of foodstuffs is effected by the addition of a small but effective amount of a flavor modifying compound from those compounds having the formula: ##STR1## wherein n is 0 or 1, R 1  is hydrogen or methyl and R 2  is methyl, ethyl, or propyl and ##STR2## wherein n is 0 or 1.

This is a division of application Ser. No. 243,866 filed Apr. 13, 1972,which is a division of application Ser. No. 70,560 filed Sept. 8, 1970,now U.S. Pat. No. 3,702,253; which latter application is a continuationof now-abandoned application Ser. No. 543,069 filed Apr. 18, 1966, whichis a continuation-in-part of now-abandoned application Ser. No. 452,342filed Apr. 30, 1965.

The invention relates to flavor agents in general. More particularly theinvention relates to chemical compounds or compositions which have beenfound to have utility in the alteration of flavor or flavorcharacteristics of substances, whether naturally occurring or synthetic.Still more particularly the invention relates to a group of chemicalcompounds which have been found to be useful in the area of flavor-notealteration, whether by the enhancement of flavors or flavor-notes thatare characteristic in a substance, by the alteration of a flavor or aflavor-note from a less to a more desirable one, or by the complete orpartial masking of a flavor or flavor-note.

As is generally recognized by those familiar with the art, the scienceof flavor technology is an extremely complex one. Although much is knownabout flavor and flavor technology there is still a great deal to belearned in the field and the body of scientific literature is beingrapidly expanded by those working in the area. The technology of flavorsynthesis and blending of various flavor elements to achieve certaindesirable results is of great commercial importance at the present stageof industrial advance. Commercial production of consumer goods fromsynthetic starting materials is becoming more and more common, anddesirable, as world population continues to increase its demands uponthe finite capacity for the production of natural products. Industry isalso continually seeking means of upgrading natural products -- methodsof altering or enhancing the qualities of taste of less desirablenatural products -- usually more abundant -- into more desirable productqualities. Often, for example, a product can be made commerciallyattractive only by masking or blanking out an undesirable flavorcomponent. Formerly, before the advent of the flavor chemist and histechnology, this unit of production would have been lost, or at least,would have had to have been re-processed to a useable quality. By theuse of specifically designed flavoring agents, however, the undesirableflavor note can be eliminated or masked with another desirable one, andthe expensive and time-consuming re-processing step eliminated or theproduction batch saved for use. Too, it is common in some segments ofthe industry, particularly the food industry, to add flavor agents toproduction units to enhance or bring out a desirable flavorcharacteristics of products -- and by so doing to render the productmore desirable from a consumer preference standpoint.

It is the object of this invention therefore, to provide the flavortechnologist with additional tools for his use in the alteration of foodflavors, whether it be flavor or flavor-note alteration generally or theenhancement or improvement of flavor or flavor notes specifically.

It is a further object of the invention to furnish a group of chemicalcompositions which have utility in the technology of flavor alteration,whether added to solid or liquid compositions for human consumption, andwhich may be used in either solid or liquid form.

A further object of the invention is to describe a group of chemicalcompounds having desirable utility as flavor agents which may beprepared synthetically, thus enabling the food technologist to alter orenhance his product without drawing upon a natural product for theflavor agent.

A still further object of the invention is to describe a group ofchemical compounds capable of synthesis from readily available organicsubstances which may be used singly or in combination to alter theflavor or flavor notes of compositions for food use, whether used inmicro-quantities such as parts-per-million or in larger quantities, asthe dictates of the end results may require.

Other objects will become apparent to those skilled in the art as thedescription proceeds.

Thus, in accordance with the concept of the instant invention, there isset out below a group of compounds which have been found to have utilityas flavor agents and to represent valuable materials to the foodtechnologist who wishes to alter the flavor components of foods or foodproducts either liquid foods or beverages, such as fruit and vegetablejuices, milk, coffee, tea, cocoa, chocolate, and the like or solid foodssuch as cereals, flours, confections, vegetables, meats, etc. The flavoragents may be used either in liquid or solid form and are used inquantities designed to give the desired results, as will be more clearlyexplained as the description proceeds.

The chemical compounds which have been found to have utility as flavoragents may be generally classified thiophene ketones.

The flavor agents or flavor modifying compositions of this invention areavailable to the food technologists in a variety of forms. It is usuallypreferable to use the agents in the form of a solution, for ease ofdilution, exactitude of measurement, efficiency of distribution in theend use, etc. However the chemical nature of the compound, itssolubility in acceptable solvents, its stability, and othercharacteristics may dictate the form in which it is used.

The amounts of the agents used is also subject to wide variation, ofcourse. More concentrated materials, and those with the greatest degreeof flavor modifying ability will be used in lesser amounts. Some degreeof experimentation is, of course, required to achieve the desiredresults. A small, but flavor modifying amount, of the agents is blendedwith the material whose total flavor is to be altered, the amountdepending upon the end result desired.

Two different types of methods were used in testing the compounds listedin this specification for their utility as flavor agents, flavormodifiers, flavor alteration agents, flavor-note enhancers, and thelike. The first type method (A) served the purpose of determining theintrinsic taste, flavor and aroma of each individual compound. Thesecond type methods (B) and (C) were used for testing the flavor- andaroma-modifying or -enhancing effects of the compounds hereinafterlisted on coffee products and more particularly on spray-dried solublecoffee products commercially known as "instant coffee".

METHOD A.

The vehicle used for testing the flavor compounds was a 65% solution ofcane sugar in tap water. The flavor compounds were incorporated in thissugar syrup in the form of 1% or 1 per 1000 by weight solutions in 96%ethyl alcohol. The concentration of the flavor compounds in the sugarsyrup varied between about 0.005 and 5 g. for 100 liters of syrupaccording to the varying strength of flavor compounds. Samples of eachflavored sugar syrup were submitted to the members of the tastingpanels. After tasting the samples each member had to give an evaluationof each flavor compound in terms of descriptive words.

In the evaluation of materials for the alteration or enhancement ofcoffee flavor or of coffee flavor notes it is essential that theequipment used, coffee pots, cups, spoons, measuring equipment, etc. beabsolutely clean prior to use.

METHOD B.

The coffee base was prepared by dissolving 1 g. of a commercialspray-dried soluble coffee in boiling water. A sufficient number of potswas prepared to provide one pot for each flavor agent to be evaluatedplus one control. The flavor agent was added to the coffee base in theform of a 1% or 1 per 1000 by weight alcoholic solution atconcentrations varying between 0.005 and 5 g. of flavor agent for 100liters of coffee base. The measured quantity of the flavor agent wasadded to a pot of the coffee base material, stirred well, and pouredimmediately into cups for the organoleptic evaluation. The taste testswere made within a short time (not more than 15 minutes) after the finalcomposition to be tested was prepared.

The organoleptic evaluation involved grading a series of cups that werecoded, the taster merely rating the coded cups against the standard orcontrol which did not contain the flavor agent. The standard was placedat the first position in a series of cups. The tasters were asked toascertain whether or not there existed differences in the flavor of thesamples to be tested as compared with the control. The tasters werefurthermore asked to describe and characterize the various flavor notesand types determined.

METHOD C.

Using boiling Crystal Spring Water, to provide a clean starting taste, a1.35% solution of relatively bland tasting commercially availablespray-dried soluble coffee was prepared. The containers used --preferably the lower portion of a glass coffee maker -- was absolutelyclean, as was the other equipment used, e.g. cups and spoons.

A sufficient number of containers, or pots, were used to accomodate eachflavor fraction to be studied, plus one control. The flavor fraction wasmeasured carefully with a micro-syringe, adding from 2 to 150microliters of the flavor fraction per pot. The mixture of coffeesolution and flavor fraction was stirred and immediately poured intocups for tasting. At least 5 experienced tasters are used. The tastingshould begin at least within 15 minutes after the solution is prepared.If not, the solution should be discarded and fresh solution prepared.

The cups are coded and the samples are not identified. A standard sampleis included in which no flavor fraction has been added. The taster isasked to identify and describe the flavor enhancement or modificationnoted.

In the following specific description of the thiophene ketones compoundsthere is first given the structural formula followed by a list ofmembers of the group which have been found to have outstanding utilityin the concept of this invention. Immediately following the chemicalname of each member there is given the commercial source or a literaturereference giving a method for its preparation. Commercially availableproducts will be identified by the abbreviation c.a., and may beobtained from FLUKA, A.G., Buchs S.G., Switzerland; ALDRICH CHEM. CO.,Milwaukee, Wis.; DR.F. RASCHIG GMBH, Ludwigshafen a. Rh., West-Germany;or K & K LABORATORIES INC., Plainview, NY. 11803.

The results of the organoleptic evaluation tests are set out in TABLE Ifollowing the detailed description of the groups of compounds.

I - THIOPHENE KETONES

Compounds of this group which have been found to have utility in theconcept of the instant invention have the following general formulae:##STR3## wherein n is 0 or 1, R₁ is hydrogen or alkyl and R₂ is alkyl;and ##STR4## wherein n is 0 or 1. Representative compounds include:

1. a. 2-acetyl-thiophene: J.A.C.S. 72, 3695 (1950)

b. 3-methyl-2-acetyl-thiophene: J.A.C.S. 72, 3695 (1950)

c. 4-methyl-2-acetyl-thiophene: J.A.C.S. 72, 3695 (1950)

d. 3-methyl-2-propionyl-thiophene: J.A.C.S. 72, 3695 (1950)

e. 5-methyl-2-propionyl-thiophene: J.A.C.S. 72, 3695 (1950)

f. 2-butyryl-thiophene: J.A.C.S. 72, 3695 (1950)

g. 5-methyl-2-acetyl-thiophene: J.A.C.S. 72, 3695 (1950)

h. 2-propionyl-thiophene: J.A.C.S. 72, 3695 (1950)

i. 2-acetylmethyl-thiophene: C.A. 51, 10509c (1957)

2. a. 5,5'-diacetyl-dithienyl-2,2'-methane: J.A.C.S. 73, 1270 (1951)

b. 5,5'-diacetyl-dithienyl-2,2': J.A.C.S. 78, 1958 (1956)

Organoleptic evaluation data are set out in TABLE I below.

                  TABLE I                                                         ______________________________________                                        Organoleptic Evaluation Table                                                 Number                                                                              Test    Quantity  Organoleptic Characterization                         ______________________________________                                        (1)a. A       1.0       onion-like taste                                      (1)a. B       0.5-1.0   malty, roasted note                                   (1)b. A       0.25      sweet honey-like taste                                (1)b. C       0.11      nutty, starchy taste                                  (1)d. A       1.0       burnt anthranilate-like taste                         (1)e. A       1.0       nonalactone-like taste                                (1)f. A       1.0       wine-like taste                                       (1)g. A       1.0       sweet, flowery taste                                  (1)h. A       2.0       cream, caramel-like taste                             (1)i. A       2.0       green, mustard-like note                              (2)a. A       4.0       sweet note                                            (2)b. A       5.0       slightly roasted note                                 ______________________________________                                    

As has been stated above the compounds having utility in the concept ofthis invention may be added to substances in varying amounts to alter orto modify the flavor of the substance by masking or blanking outundesirable flavors, by enhancing or fortifying desirable flavor orflavor notes, or by adding to the original substance an entirely new anddifferent flavor. As will also be apparent to those skilled in the artvarious mixtures or blends of the flavor agents described may be used toachieve a desired flavor or flavor note. If, for example, one wishes toenhance a certain flavor note, or group of flavor notes present in asubstance such as coffee, one needs only mix together certain of thedescribed flavor agents to obtain the desired result.

It should be kept in mind, as will be appreciated by thoseskilled-in-the-art, that with many flavors it is possible to imitate thenatural flavor by selecting a limited number of the flavor enhancingsubstances examplified above. Coffee aroma, on the other hand, is muchmore complex than the ordinary flavoring materials and may necessitatethe combination of many more of the examplified ingredients forreproduction.

It will also be understood that whereas the preferred embodiment of thisinvention is directed toward the enhancement or modification of coffeeflavors, the concept of the invention has much wider application. Whilesome of the compounds may be characterized by terms which are notdirectly related to coffee flavors, these compounds, when used in morecomplex formulae, may contribute desirable flavor notes to the overallflavor and aroma.

To summarize briefly this invention relates to a group of chemicalcompounds which have been found to have utility for the alteration ormodification of the flavor of other materials. These compounds, calledflavor agents or flavor modifiers, may be used in minute quantities toenhance the natural flavor of substances to which they are added, or toalter or modify a flavor which is undesirable, or to impart to asubstance additional or different flavors or flavor notes. The flavoragents of the invention are used in minor, but flavor altering amounts,in any case, in quantities sufficient to obtain the desired results. Theflavor modifiers are of particular importance and usefulness in themodification, alteration or enhancement of the flavor of coffeebeverages made from soluble coffee and the preferred embodiment of theinvention contemplates their use in conjunction with such products.

The flavor agents of the invention may be added at a convenient step inthe soluble coffee process such as plating the dried soluble coffee witha desired dilution of the flavor agent in an acceptable solutionfollowed by drying. In certain instances the desired agent may be addeddirectly to a concentrated coffee extract and the mixture dried into asoluble coffee product which contains the flavor agent as an integralpart thereof. Other methods of incorporation of the agents will suggestthemselves to those skilled in the art and may, of course, be usedwithout departing from the inventive concept, which may be described asbeing a composition of matter comprising a combination of a solublecoffee product, however prepared, whether liquid or solid, concentratedor dilute, which contains combined therewith a minor, but flavormodifying amount, of a flavor agent as described herein.

What is claimed is:
 1. As a new composition of matter a soluble coffeematerial having added thereto a minor, but flavor-modifying amount of acompound selected from the group of compounds having the generalformula: ##STR5## wherein n is 0 or 1, R₁ is hydrogen or methyl and R₂is methyl, ethyl or propyl; and ##STR6## wherein n is 0 or
 1. 2. Thesoluble coffee of claim 1 wherein the added compound is2-acetyl-thiophene.
 3. The soluble coffee of claim 1 wherein the addedcompound is 3-methyl-2-acetyl-thiophene.
 4. The soluble coffee of claim1 wherein the added compound is 4-methyl-2-acetyl-thiophene.
 5. Thesoluble coffee of claim 1 wherein the added compound is3-methyl-2-propionyl-thiophene.
 6. The soluble coffee of claim 1 whereinthe added compound is 5-methyl-2-propionyl-thiophene.
 7. The solublecoffee of claim 1 wherein the added compound is 2-butyryl-thiophene. 8.The soluble coffee of claim 1 wherein the added compound is5-methyl-2-acetyl-thiophene.
 9. The soluble coffee of claim 1 whereinthe added compound is 2-propionyl-thiophene.
 10. The soluble coffee ofclaim 1 wherein the added compound is 2-acetylmethyl-thiophene.
 11. Thesoluble coffee of claim 1 wherein the added compound is5,5'-diacetyl-dithienyl-2,2'-methane.
 12. The soluble coffee of claim 1wherein the added compound is 5,5'-diacetyl-dithienyl-2,2'.
 13. Aprocess for the alteration of the natural flavor of soluble coffeematerial which comprises adding thereto a minor, but flavor-modifyingamount of a compound selected from the group of compounds having thegeneral formulae: ##STR7## wherein n is 0 or 1, R₁ is hydrogen or methyland R₂ is methyl, ethyl, or propyl; and ##STR8## wherein n is 0 or 1.14. The process of claim 13 wherein the added compound is2-acetyl-thiophene.
 15. The process of claim 13 wherein the addedcompound is 3-methyl-2-acetyl-thiophene.
 16. The process of claim 13wherein the added compound is 4-methyl-2-acetyl-thiophene.
 17. Theprocess of claim 13 wherein the added compound is3-methyl-2-propionyl-thiophene.
 18. The process of claim 13 wherein theadded compound is 5-methyl-2-propionyl-thiophene.
 19. The process ofclaim 13 wherein the added compound is 2-butyryl-thiophene.
 20. Theprocess of claim 13 wherein the added compound is5-methyl-2-acetyl-thiophene.
 21. The process of claim 13 wherein theadded compound is 2-propionyl-thiophene.
 22. The process of claim 13wherein the added compound is 2-acetylmethyl-thiophene.
 23. The processof claim 13 wherein the added compound is5,5'-diacetyl-dithienyl-2,2'-methane.
 24. The process of claim 13wherein the added compound is 5,5'-diacetyl-dithienyl-2,2'.
 25. Acomposition selected from the group consisting of foodstuffs andbeverages to which has been added an effective flavor-improving amountof a compound selected from the group of compounds having the generalformulae: ##STR9## wherein n is 0 or 1, R₁ is hydrogen or methyl; and R₂is methyl, ethyl or propyl; and ##STR10## wherein n is 0 or
 1. 26. Thecomposition of claim 25 wherein the added compound is2-acetyl-thiophene.
 27. The composition of claim 25 wherein the addedcompound is 3-methyl-2-acetyl-thiophene.
 28. The composition of claim 25wherein the added compound is 4-methyl-2-acetyl-thiophene.
 29. Thecomposition of claim 25 wherein the added compound is3-methyl-2-propionyl-thiophene.
 30. The composition of claim 25 whereinthe added compound is 5-methyl-2-propionyl-thiophene.
 31. Thecomposition of claim 25 wherein the added compound is2-butyryl-thiophene.
 32. The composition of claim 25 wherein the addedcompound is 5-methyl-2-acetyl-thiophene.
 33. The composition of claim 25wherein the added compound is 2-propionyl-thiophene.
 34. The compositionof claim 25 wherein the added compound is 2-acetylmethyl-thiophene. 35.The composition of claim 25 wherein the added compound is5,5'-diacetyl-dithienyl-2,2'-methane.
 36. The composition of claim 25wherein the added compound is 5,5'-diacetyl-dithienyl-2,2'.
 37. Aprocess for the alteration of the flavor of a composition selected fromthe group consisting of foodstuffs and beverages which comprises addingthereto a minor, but flavor-modifying amount of a compound selected fromthose represented by the general formulae: ##STR11## wherein n is 0 or1, R₁ is hydrogen or methyl and R₂ is methyl, ethyl or propyl; and##STR12## wherein n is 0 or
 1. 38. The process of claim 37 wherein theadded compound is 2-acetyl-thiophene.
 39. The process of claim 37wherein the added compound is 3-methyl-2-acetyl-thiophene.
 40. Theprocess of claim 37 wherein the added compound is4-methyl-2-acetyl-thiophene.
 41. The process of claim 37 wherein theadded compound is 3-methyl-2-propionyl-thiophene.
 42. The process ofclaim 37 wherein the added compound is 5-methyl-2-propionyl-thiophene.43. The process of claim 37 wherein the added compound is2-butyryl-thiophene.
 44. The process of claim 37 wherein the addedcompound is 5-methyl-2-acetyl-thiophene.
 45. The process of claim 37wherein the added compound is 2-propionyl-thiophene.
 46. The process ofclaim 37 wherein the added compound is 2-acetylmethyl-thiophene.
 47. Theprocess of claim 37 wherein the added compound is5,5'-diacetyl-dithienyl-2,2'-methane.
 48. The process of claim 37wherein the added compound is 5,5'-diacetyl-dithienyl-2,2'.